1. Field of the Invention
The present invention concerns a method to operate a magnetic resonance system of the type having at least one control device fashioned for image data acquisition, and corresponding components.
2. Description of the Prior Art
Computerized procedures known as measurement protocols are typically used to operate a magnetic resonance system. In addition to the measurement sequence defining the temporal arrangement of radio-frequency pulses, magnetic field gradients and acquisition points in time, are all relevant control parameters which are defined in these measurement protocols. When the system operator loads such a protocol, he or she can begin the measurement (i.e. the diagnostic imaging) data acquisition with the preset control parameters; otherwise the operator is forced to set the control parameters more or less by hand.
The control parameters include parameters whose meaning can easily be determined, for instance the layer thickness. For other control parameters, however, the effects when changed by the operator are not readily apparent. The bandwidth of the radio-frequency pulses is an example of the latter case.
In every case, the possibility for improved adjustment of the data acquisition requires a significant degree of background knowledge.
It is also typical to store a single sequence (for example a FLASH sequence) with control parameters respectively modified for different purposes in various protocols. In addition to the sequence, a protocol thus also contains the specific control parameters, for instance the echo time or the repetition time. Differences in the use result, for example a triggering of the measurement data acquisition is generally required in measurements of the heart, but this triggering that can be suppressed in measurements in the abdomen or in the brain. In spite of the presence of a specific sequence in the memory device of the control device, the stored sequence is thus not optimized for all possible applications. It further complicates matters that a number of sequences are known in magnetic resonance tomography. For example, an expert in the field of measurements of the brain would normally not be able, without further measures to correctly set a measurement sequence for acquisition of the heart, (an “expert” being a person with background knowledge of the physics and data acquisition by means of magnetic resonance tomography). The generation of new protocols with existing sequences is accordingly even more complicated for physicians or medical technology employees. Problems also arise when apparatuses of different manufacturers are used. Normally no uniform names from manufacturer-to-manufacturer are provided for identical sequences, such that a user can have problems upon operation if he or she must operate with a new apparatus that is possibly unknown to the operator or is only rarely used.
Known methods for automation of the magnetic resonance measurements do not provide assistance in this regard. For example, it is known to automatically detect the position and orientation of a patient. It is also known to automatically evaluate measurement data in order to generate from these control parameters for the next data set to be acquired. However, this requires that this data set is already defined to the greatest possible extent. For example, if the precise position of an organ to be acquired is determined from an overview image, the control parameters to be set are basically apparent in the slice positioning, but all additional control parameters necessary for data acquisition must be known beforehand, or must be stored as a protocol.